Actuator for machine guns



Apr. 17, N23.

1,452,465 M. L. JOHNSTON ACTUATOR FOR MACHINE GUNS Original Fil-ed Jan. 1918 INVENTOR. MLLLARD .L. JOH/VJTO/V ATTORNEY.

Patented Apr. 17, 1923.

STATES MILLARD L. JOHNSTON, 0F UTICA, NEW YORK.

ACTUATOR FOR MACHINE GUNS.

Application filed January 8, 1818, Serial No. 210,912. Renewed February 28, 1923.

To all whom it may concern Be it known that I, ldrLLlini) L. JOHNSTON, citizen of the United States, residing at Utica, in the county of Oneida and State of New York, have invented certain new and useful Improvements in Actuators for Ma chine Guns, of which the following is a specification, reference being had therein to the accompanying drawing.

My invention relates to an actuator for machine guns and I declare the following to be a full, clear, concise and exact description thereof sufiicient to enable anyone skilled in the art to which it. appertains to make and use the same, reference being had to the accompanying drawings in which like reference characters refer to like parts throughout the specification.

The object of the invention is to provide a device that will lock the firearm in a secure manner against accidental explosion until the cartridge has been moved into its chamber in the barrel. To this end a dog having a depending projection is employed to hold the hammer from striking the end of the firing pin until the breech bolt has pushed the cartridge home into its chamber in the barrel.

The object will be understood by referring to the drawings in which:

Fig. 1 is a vertical section of the rear portion of a machine gun, showing the application of the actuator;

Fig. 2 is a detail perspective view of a part of a'piston rod employed, showing the hammer connected thereto;

Fig. 3 is a detail view, showing a perspective of a bolt carriage employed;

Fig. 1 is a detail showing a perspective View of a locking dog employed;

Fig. 5 is a detail showing a perspective view of a detachable collar employed.

Referring more particularly to the drawings, the chambered portion of a machine gun such as that illustrated in the application of James S. Johnston, filed April 3, 1917, and numbered serially 159,533 is represented by 1, the cartridge carrier by 2, which carrier revolves upon the piston tube 3, and the barrelby 1-, as more fully described in the above referred to application.

Vithin the tube 3 is the usual piston and piston rod 5 actuated by the gases of explosion, whereby to cock the gun. The rear end of the piston rod 5 is headed at 6. An

upright hammer 7 having a striking part 8, the upper edge of which is rounded off at 9, is adapted to actuate the firing pin 10 at the proper time. Theupright hammer is movable with the piston rod 5 and within a recess 11 formed in the part 12 of the bolt carriage 13. The part 12 is made integral with a sleeve 17 through which projects in a loose manner the piston rod 5.

The part 12 of the bolt carriage 13 is equipped with the lateral flanges 1414 that fit within correspondingly formed guide grooves in the sides of the firearm, whereby to guide the longitudinal movement of the carriage 13. Recesses 15 are cut into the sides of the part 12 for the entrance of certain dogs, not shown, for locking the breech bolt 16, containing the spring retracted firing pin 10, in firing position. The beveled shoulders 18 are intended to force or wedge the dogs, not shown, outwardly, whereby to release the breech bolt, after the firing has occurred, as is more fully described in the above referred to application.

The part 12 of the carriage 13 has a sunken recess 20 into which projects 2. lug 21 depending from the breech bolt 16, whereby said breech bolt 16 will move with the motion of the carriage 13. A shoulder 19 spaces the end of the breech bolt 16 from the adjacent surface of the carriage 13.

The upper part of the portion 12 of the carriage 13 is recessed for the pivotal mounting of the locking member or dog 22, which has trunnions 23-23 upon which it is fulcrumed. A depending lug 40 with a rounded surface is adapted, in cocked position of the gun, to hang down in front of the part 8 of the hammer 7,.whereby to hold the hammer against the pressure of the coiled main spring 23 located in the rear portion of the tube 3, which extends into the stock of the gun, as is well known in the art.

The piston rod 5 is reduced at 24 over which reduced part is mounted a detachable collar 25 adapted to move with the piston rod 5. The collar 25 will abut against the contiguous edge of the sleeve 17 and move the same together with thecarriage 13 and breech bolt 16 rearwardly with the motion or" the piston rod 5.

The operation of the device is as follows: Assuming the parts of the firearm to be in cocked position. as illustrated in Fig. 1, and the trigger 27, is then pulled, to retract the sear plunger 26, the main spring 23 will push the piston rod 5 and the parts connected therewith, that is the sleeve 17, the bolt carriage l3 and breech block 16 forward, whereby to dispose a cartridge Within the chamber of the barrel at. Immediately, the breech bolt 16 arrives in the latter named position, where the cartridge is pushed into the chamber 30, the locking dog 22 will' ride up into the recess 33 formed in the casing 3% of the firearm 'because of the pressure exerted by the adjacent portion of the upright hammer 7 vhich is indirectly acted upon by the main spring 23. is the locking dog 22 moves up into the recess 33, the upright hammer 7 will fly forward under the pressure of the main spring 23 and cause the part 8 of said hammer 7 to strike the end of the firing pin 10. The forward end of the firing pin 10 will, thereupon, strike and explode the cartridge. Immediately after the explosion occurs the gases thereof will effect a retroaction move ment of the piston and piston rod 5. The piston rod 5 will move back a given distance to permit the return of the firing pin 10 to normal position under pressure of the coiled spring and to permit the locking dog 22 to turn on its trunnions 23, the same being forced down by the contiguous surface of the casing l--, as the breech bolt 16 moves to the rear, whereby the lug will drop down in front of part 8 of the hammer 7. The retraction of the firing pin 10 and dog 22 Will occur before the bolt carriage l3 begins to move rearwardly with. the piston rod 5.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. In an actuator for machine guns having a casing, a breech bolt containing a firing pin, a piston carrying a hammer, a dog having a depending lug-adapted to lie in front of said hammer, and a recess in said casing whereby said hammer canslip by said lug to strike the firing pin.

2. In an actuator for machine guns, a breech bolt carrying a firing pin, a-bolt carriage having a recess, a hammer adapted to move in said recess, a dog having a tie pending lug adapted to prevent the hammer from striking the firing pin, and means for permitting said hammer to slip past said depending lug, whereby to strike the firing pin.

3. In an actuator for machine guns, a breech bolt carrying a firing ,pin, a bolt carriage for controlling the movements of said breech bolt, a hammer for striking said firing pin, a dog for holding said hammer in given position for a predetermined time and means for permitting said hammer to slip by said dog, whereby to strike the firing pin.

In testimony whereof I have affixed my signature.

MILLARD L. JOHNSTON. 

